Agitator of a liquid sample

Abstract

An agitator by vibrations includes an annular resonator to which is applied a vibratory stress by piezoelectric transducers. A preferred stress shape is a bending of the ring perpendicularly to its plane to excite inherent modes at relatively low frequencies. Use of a solid annular transmitter enables the vibrations to be satisfactorily controlled to maintain satisfactory transmission to the sample to be agitated, and to focus them on it. Excitation frequencies are frequencies inherent to the ring or to the tank.

1 - 24 . (canceled) 
     
     
         25 . An agitator of a liquid sample, comprising:
 a tank containing the sample; and   a vibration generator, wherein vibrations are communicated to the tank by an intermediate medium,   wherein the intermediate medium is a solid ring resonator surrounding the tank and combined with the tank, and   wherein the tank is attached to the center of the ring, and the vibration generator includes at least one piezoelectric transducer installed in a peripheral region of the ring and constructed to transmit vibrations in a radial direction of the ring to the ring and to the tank.   
     
     
         26 . An agitator of a liquid sample according to  claim 25 , wherein the tank is a tube with an axis perpendicular to the ring. 
     
     
         27 . An agitator of a liquid sample according to  claim 26 , wherein the tube has opposite ends attached to a fixed frame. 
     
     
         28 . An agitator of a liquid sample according to  claim 27 , wherein the resonator is attached to the frame at a periphery of the ring. 
     
     
         29 . An agitator of a liquid sample according to  claim 27 , wherein the resonator is suspended from the frame by an elastic structure. 
     
     
         30 . An agitator of a liquid sample according to  claim 27 , wherein the resonator is suspended from the tube and is independent of the frame. 
     
     
         31 . An agitator of a liquid sample according to  claim 27 , wherein ends of the tube are attached to the frame, and are supported on rubber discs. 
     
     
         32 . An agitator of a liquid sample according to  claim 31 , wherein the frame includes holes revealing the rubber discs, and the ends of the tube are open. 
     
     
         33 . An agitator of a liquid sample according to  claim 26 , wherein the tube includes an inner face with a helical bore. 
     
     
         34 . An agitator of a liquid sample according to  claim 25 , wherein the ring tapers from its periphery towards the tank. 
     
     
         35 . An agitator of a liquid sample according to  claim 25 , wherein the resonator includes a central sleeve of axis perpendicular to the ring, and the tank is gripped in the sleeve. 
     
     
         36 . An agitator of a liquid sample according to  claim 35 , wherein the tank is a tube with an axis perpendicular to the ring and the tube is conical. 
     
     
         37 . An agitator of a liquid sample according to  claim 25 , wherein the vibration generator includes multiple transducers controlled separately. 
     
     
         38 . An agitator of a liquid sample according to  claim 25 , wherein the transducer delivers vibrations at different frequencies. 
     
     
         39 . An agitator of a liquid sample according to  claim 37 , wherein a group of transducers extends over respective sectors of an arc of a peripheral area of the ring, and delivers vibrations of identical frequency with phase shifts identical to angular shifts between sectors of an arc. 
     
     
         40 . An agitator of a liquid sample according to  claim 37 , wherein the transducers are positioned on two opposite faces of the ring. 
     
     
         41 . An agitator of a liquid sample according to  claim 40 , wherein the resonator includes a central sleeve of axis perpendicular to the ring, the tank is gripped in the sleeve and the vibrations delivered by the transducers positioned on the opposite faces of the ring have component elements in antiphase, and thus produce a bending of the ring. 
     
     
         42 . An agitator of a liquid sample according to  claim 25 , wherein the vibration generator includes a complete circular transducer delivering a symmetrical vibration producing an oscillating compression of the tank. 
     
     
         43 . An agitator of a liquid sample according to  claim 42 , wherein a group of transducers extends over respective sectors of an arc of a peripheral area of the ring, and delivers vibrations of identical frequency with phase shifts identical to angular shifts between sectors of an arc, the transducers are positioned on two opposite faces of the ring and the agitator includes the group of transducers on one of the faces and a complete circular transducer on the opposite face. 
     
     
         44 . An agitator of a liquid sample according to  claim 35 , wherein the sleeve tapers from a place of connection to the ring as far as at least one end. 
     
     
         45 . An agitator of a liquid sample according to  claim 44 , wherein the sleeve has a thickness equal either to half a thickness of the ring, or to the thickness, depending on whether it has two ends, or one end, and a zero thickness at the other end. 
     
     
         46 . An agitator of a liquid sample according to  claim 34 , wherein the transducers of the group are four in number, their vibrations are shifted by a quarter phase, and they extend over angular sectors of 70°. 
     
     
         47 . An agitator of a liquid sample according to  claim 26 , further comprising a magnet adjacent to the tube and to the ring. 
     
     
         48 . An agitator of a liquid sample according to  claim 29 , wherein the transducer is piezoelectric.